[R] Sorting based a custom sorting function

[Martin Møller Skarbiniks Pedersen]

Hi,

  I need to sort a data.frame based on a custom sorting function.
  It is easy in many languages but I can't find a way to do it in R.

  In many cases I could just use an ordered factor but my data.frame
contains poker hands and
I need to rank these hands. I already got a function that compares two hands.

Here is a MRE (Minimal, Reproducible Example):


df <- data.frame(person = c("Alice", "Bob", "Charlie"), value =
c("Medium", "Small", "Large"))

# 0 means equal, -1 means left before right, 1 means right before left
custom_sort <- function(left, right) {
  if (left == right) return(0)
  if (left == "Small") return(-1)
  if (left == "Medium" & right == "Large") return(-1)
  return(1)
}

#  sort df according to custom_soft
# expect output is a data.frame:
#     name   size
# 1     Bob Medium
# 2   Alice  Small
# 3 Charlie  Large

In this simple case I can just use an ordered factor but what about
the poker hands situation?

Regards
Martin